Reprogramming key fob

Hello there
My key fob gave up so I bought a complete new unit (ebay) with blank key and following the instructions on here have been able to reprogram it so it locks/unlocks as expected.
I thought I would then be able to put the old key with the new fob to have a functioning unit but the immobiliser will not let me start the car, so at present have 2 complete keys on my key ring, new one to open and old one to start it.
Is that just life or am I missing a trick.
Many thanks in advance guys.

Damon

Hello Damon,

Programming the immobiliser is a separate process and you must have 2 keys which already start the car to be able to program the third.

If you don't have 2 keys which already start the car then you'll need to get it programmed by an auto locksmiths or Ford.

Welcome to the site.

OH you can take the transponder our of your old key and put it in the new key (killing the old key) but that will make the new one start the car!

It's a little glass tube wrapped in rubber, be mindful not to break it else you'll have 2 keys which don't start the car!

i had this issue when my remote key broke, you need to remove the transponder from the key that starts the car and put it into the new key (replacing the one that is in there at the moment). you also need to swap the actual key blades over so you can unlock the doors manually as well...

unfortunately i don't have a spare key to take pics and show you how to remove it, you have to be careful because its glass. either that or you have to pay for any auto lock smith to reprogram they key for you...

I swapped the transponder and key blade round it only took 5 mins... i will have a quick look and try to find some pics or a guide...

EDIT: dam you beat me to it

Right Bingo....

you need to cut carefully along the rubber bit circled in red in the pic below:



until you are able to remove the transponder (from the key that starts your car). It is glass so be careful...

the transponder looks like this:



when you have removed the old one (the one you need) do the same to the new key to remove the transponder that isnt programmed to your car. (you can do this key first its up to you).

once that is out put the transponder that works into the new key (make sure its the right way round)...

put the key back together (make sure you have the correct key blade to open your doors manually) and go test it out...

you should now have one full functioning key and one that does nothing to your car at all...

you can then stick the rubber bit back down carefully if you need to.

when i did mind it kind of just slipped into the top opening so i didn't need to cut the new key.

hope this helps k:

Damn. I only have the one key and could do with another just in case. Luckily for me, I know my limits and will not attempt to dismantle my key as I know it will not end well. I imagine than, my only option is to pay a ridiculous fee to Ford for them to press a few buttons.

it is pretty easy to do... if you really want someone to reprogram a new one get an auto locksmith to do it... you can even get mobile (search for mobile auto locksmiths) ones to come to you to do it... will take them like 5 mins and will be cheaper for sure...

What a response! Brilliant, thank you so much guys, it's really appreciated. Now to work some magic ha ha.

"Pretty easy to do" for you probably isn't pretty easy for me, although I did once take a computer to PC World to install some new RAM even after seeing a diagram of how to do it and everything, which it turned out is the easiest job in the world.

Sorry to drag up an old thread

Yes I’m still struggling with the fact the I threw the only key away

Can someone confirm what chip goes in an early puma (glass or plastic) and how do locksmiths program the key ? Do they need the ecu or something?

Hi Vince,

It's glass "red" and yes the key code needs to be extracted / coded from the ECU using the ODB diagnostic port.

Great key info in ->this<- thread